Expandable honeycomb structures have been utilized for many years successfully as window coverings and frequently are constructed of two separate pleated sheets which are secured together with or without joining strips. In other cases a plurality of tues are separately formed and thereafter joined together in serial fashion. An example of one expandable honeycomb structure is shown in the Colson, U.S. Pat. No. 4,603,072. Colson produces his honeycomb structure by feeding one roll of a narrow strip or tape toward a creasing device. Tubular elements are formed by looping the material and the resulting tubular structure is wound in roll-like form on a rotating device.
While the Colson method provides a satisfactory set of honeycomb structures, it is limited in the size of the honeycomb and the height of the stacking and moreover utilizing his method it is difficult to clear extra glue in the middle of the tubular cells because of the cell configuration and also because of winding the completed honeycomb onto a loading roller.
Another disadvantage in the Colson construction is that his method is limited to forming a honeycomb cellular structure of about 3/4 inches and therefore it is necessary in order to build cells to join the short cells together axially, or more particularly to stack sets of cells on top of one another.
It is a primary object of the present invention to ameliorate the problems noted above in forming pleated honeycomb panels.